Color Identity: B

Initial Card State
- Activated Sleeper in your graveyard.
- Cavalier of Night and Ashnod's Altar on the battlefield.
Steps
- Activate Ashnod's Altar by sacrificing Cavalier of Night, adding ({C} magic symbol)
({C} magic symbol)
. - When Cavalier of Night dies, it triggers, returning Activated Sleeper from your graveyard to the battlefield as a copy of Cavalier of Night.
- When Activated Sleeper enters the battlefield, it triggers; choose not to sacrifice a creature.
- Activate Ashnod's Altar by sacrificing Activated Sleeper, adding ({C} magic symbol)
({C} magic symbol)
. - When Activated Sleeper dies, it triggers, returning Activated Sleeper from your graveyard to the battlefield as a copy of Cavalier of Night.
- Repeat from step 3.
Results
- Infinite colorless mana.
- Infinite death triggers.
- Infinite ETB.
- Infinite LTB.
- Infinite sacrifice triggers.
Bracket Tag
This combo has been estimated to be Exhibition (Bracket 1+).